Platinum contact.



ANTON FREIER, OF

BOSTON, MASSACHUSETTS, ASSIGNOR TO HOLTZER CABOT ELECTRIC COMPANY, A CORPORATION OF MASSACHUSETTS.

PLATINUM CONTACT.

To all whom it may concern:

Be it known that I, ANTON FREIER, a citizen of the United States, residing in Boston, in the county of Suffolk and State of Massachusetts, have invented an Improvement in Platinum Contacts, of which the following description,-in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

The present invention relates to a contact tip, and is shown embodied in an electrical contact in which a very thin piece of sheet platinum is applied to the contact member at the actual point of contact, the purpose of the invention being to utilize the qualities of the platinum to advantage, with the employment of the least possible quantity of platinum to save expense.

For convenience in the following description, the term platinum will be employed,

with the understanding that this is the metal now commonly employed for electrical contact tips, it being within the invention to employ other metals for similar or other purposes.

the compound strip of platinum and other metal in an opening formed in the contact member, with a driving fit, so that the parts are firmly "held together, the covered portion protecting the surface of the contact member to form the actual contact portion thereof.

A simple and practicable method of" applying the platinum tip consists in punching a piece out of the compound strip of metal, and, at the same operation, forcing the punched-out part into or partly through a ole in the contact member, so that the lati num surface projects slightly beyond the surface of the main member while the body of the punched-out part is securely held by a frictional fit in the hole.

Whileit is obvious that the same result ma beobtained in other ways, the article em odying the invention will be described .as made in accordance with the aforesaid Specification of Letters Patent. Application filed May 13.190'7- Serial No. 373.210-

Patented Nov. 19, 1907;

method, in order to facilitate the understanding of the invention.

Figure 1 is" a section of a compound strip formed of platinum and other metal, such as German silver, which forms the base or support for the platinum; Fig. 2 is a sectional view showing a punch and die with the contact member and platinum strip applied thereto, and the platinum contact part forced into position; Fig. 3 is a sectional view of the finished contact member; Fig. 4 is a view similar to Fig. 2 showing a modified form of contact member; and. Fig. 5 is a view partly in section and partly in elevation of such modified contact member finished.-

The article embodying the invention consists, as best shown in Fig. 3, of the thin coating a of platinum which is caused to adhere to a supporting body I) of a different metal 'such as German silver, or other metal less valuable than platinum, the parts a and b being frictionally secured in a metallic contact member 0 with the surface of the platinum part a shown as protruding beyond the surface of the member 0 to form the actual en aging part of the contact arm.

'n constructing the contact member, the parts a and b may first be united in the form of a sheet, as shown in Fi 1, and the actual portion of said sheet which is to form the engaging part of the contact member 0 may be cut out by means of a punch d, and, at the same time, inserted in a hole or opening in the member 0.

As indicated in Fi 2, the member 0, reviously provided with a hole 0 of the ri ht size, maybe placed upon a support e wit 1 a compound strip a, b between it and the punch d, the support e being provided with anopening 6 in alinement with the punch d and with the opening in the member 0, so that the punched-out part of the compound strip can be forced entirely through the member 0 until the part 0 projects beyond the under surface thereof. In the actual punching process, the hole 0 in the member a constitutes the female punching die, so that the piece cut out will be forced with a ti ht frictional fit through the hole, and the p atinum strip will be drawn back around the edge, so that while the metal protrudes far enough to form the projecting contact tip, the platinum itself will be artly within the opening and frictionally he d therein so that it will not become separatedjrom the rest of the contact if unduly heated. For this reason, the thin strip of latinum can be brazed-to the surface of t e body portion 1), and the two can be separated after a number of contact pieces have been punched out by dissolving oil, or otherwise removing the German sil.-

ver, or other metal, so as to waste none of the more costly material. the contact tip is Wholly, of platinum, al though a minute quantity of platinum is I used, so that all the advantages of a plat istructlon is illustrated inFigs. 4 and 5 in 5 which the actual platinum contact part a is shown as at the end of a pin or screw 0.

By this construction,

support of different metal, the compound tip thus formed being frictionally secured in an opening in thecontact member, with the edge of the platinum coating within the opening. 2. As an article of manufacture, a metallic member provided with an opening, and a connected part formed of two metals joined together and fitted tightly in the opening with the edges of both metals within the opening and the surface formed of one ofsaid metals projecting outward fromthe surface of the metallic member. In testimony whereof, I have signed my name to this specification inthe presence of two subscribing witnesses.

ANTON FREIER. Witnesses:

IIENRY J. LIvERMoRE, JAMns J. MALONEY, 

